In testing a certain kind of truck tire over rugged terrain, it is found that 25% of the trucks fail to complete the test run without a blowout. Of the next 15 trucks tested, find the probability that

a. from 3 to 6 have blowouts

b. fewer than 4 have blowouts;

c. more than 5 have blowouts.

Use the Binomial table from the back of the book.